Recently, HIV (human immunodeficiency virus) protease inhibitors have been developed for treatment of AIDS (acquired immune deficiency syndrome). With combined use of the protease with either of two HIV reverse transcriptase inhibitors which have been commonly used, treatment of AIDS has made remarkable progress. However, the treatment is still not efficient enough, and development of a new anti-AIDS medicine based on a different mechanism of action is desired.
As a receptor when HIV invades a target cell, CD4 has already been known. Recently, new receptors, CCR5 as a second receptor of macrophage directed HIV, and CXCR4 as a second receptor of T cell directed HIV, a G-protein conjugated chemokine receptor having a seven-transmembrane protein structure, have been found, suggesting a critical role of these chemokine receptors for infection and transmission of HIV. As a matter of fact, it has been reported that a man having resistance to infection even after repeated exposures to the virus had a mutation in which CCR5 gene was deleted homologically. Thus, the CCR5 antagonists have a potential to provide a new HIV medicine, and examples of synthesis of new anilide derivatives having CCR5 antagonist activity have been reported in, for example, PCT/JP98/05708 (WO99/32100), Japanese Patent Application No. 10-234388 (WO00/10965), and Japanese Patent Application No. 10-363404 (PCT/JP99/07148), while there has been no report of a CCR5 antagonist which has been commercialized as a therapeutic medicine for AIDS. Further, a compound having CCR5 antagonist activity has been described as useful as a preventative medicine of AIDS in JP 2001-026586 A, but said compound has a different structure from the compound of the present invention.